Agricultural applications of anhydrous ammonia are in some examples provided by way of an applicator including a series of knives (or coulters) and dispensing orifices associated with each of the knives. The ammonia is dispensed in a liquid or gaseous form into the cuts formed by the knives. The anhydrous ammonia is stored in one or more tanks, and the tanks are pulled in an implement train including, for instance, a prime mover such as a tractor, the applicator, and an ammonia tender. The vapor pressure within the tanks gradually decreases as ammonia is drawn from the tanks. The decrease in vapor pressure allows the remaining ammonia to transition from a liquid phase to a liquid and vapor phase. As the ammonia within the tanks is depleted the remaining ammonia transitions further toward a vapor phase.
For the proper application of anhydrous ammonia, liquid ammonia is desired for delivery to the dispensing orifices and deposition within the cut soil. Heat exchanger systems are used (e.g., on the applicator) to cool the ammonia and transition the vapor and liquid mixture toward a liquid phase. In some examples, the heat exchangers deliver a refrigerant (for instance recycle ammonia) through a linear tube extending through a passage for the ammonia. Heat transfer between the linear tube and the ammonia cools the ammonia and transitions the vapor component of the mixture toward the liquid phase. The ammonia is delivered to a distributor (e.g., with a pump), and from the distributor to the dispensing manifolds or orifices on the applicator. In another example, a series of vertical dams or baffles are provided in the ammonia passage to facilitate heat transfer with a serpentine flow of the ammonia.